Glycemic Index and Load

Often when people begin to look at their nutrition more closely they come across glycemic index and glycemic load. They hear or read that you need to make sure to eat foods that are low on both scales and avoid everything else. But as you’ll see in the next few paragraphs they’re not quite the same and the numbers for both can be conflicting.

What Are They?

The glycemic index (GI) gives a food a score on a scale of 0-100 for how quickly it is digested and released as sugar into the blood stream. Pure glucose (sugar) is given a score of 100. Lower GI foods cause your blood sugar to rise at a slower rate after eating that food. Higher GI foods cause the blood sugar to rise quicker. Glycemic load (GL) gives a more accurate assessment of how a food will impact your blood sugar levels. It does this on a ranking scale also but it measures the amount of carbohydrates in a serving of a particular food. Foods with a low GL rank from 0-10 and have very little impact on your blood sugar. A GL between 10-20 will have a moderate impact and a high GL over 20 can cause a sugar spike.

Watermelon As An Example

Watermelon is a very good example of a carbohydrate with a high glycemic index of over 70 but a low glycemic load under 10. The GI is high because it’s based on lots of watermelon but an actual serving of it has a GL of just 7. This is because watermelon is mostly water! Lower GI and GL foods tend to have more fiber and nutrients in them and help keep our energy levels more balanced throughout the day.

Insulin Release

You can still get a blood sugar spike from eating a lot of a low or moderate GL food however and so it’s also important to know the correct amounts to eat. When your blood sugar rises dramatically your body releases insulin to bring it back down. When this happens too frequently it can lead to insulin resistance and in some cases type 2 diabetes. There are many things that have an influence on your absorption of sugar from foods and their reaction on insulin release.

These things include;

  • Your fitness level
  • Amount of body fat you have
  • Genetics
  • Gut health
  • Amount of muscle you have
  • Whether you’ve trained recently, how hard and how long you trained
  • The time of day
  • What else you ate in a particular meal

The Take Home Message

Taking all of this into consideration I feel using the GI or GL is kind of over complicating things. If you want to improve your health and fitness just focus on doing the basics well and consistently. Eat mostly minimally processed foods that are higher in nutrients. Make sure you’re getting enough protein and vegetables. Exercise consistently and aim to improve your strength or fitness levels. When you can get more/improve sleep, do so. Give yourself a break now and then to try and manage stress. Keep things simple and enjoy the process without complicating things.

Leave a Comment


Your email address will not be published. Required fields are marked *